Examples of a vehicle air-conditioning apparatus used in a vehicle, such as a train, include a ceiling-mounted one which is embedded in a ceiling of a vehicle and a rooftop one which is placed on a roof of a vehicle. Such a vehicle air-conditioning apparatus includes a compressor, a condenser, an outdoor blower, an evaporator, an indoor blower, an electrical component box, and the like. A return port for taking in in-vehicle air is provided at a lower portion of the vehicle air-conditioning apparatus. The electrical component box which houses, for example, an inverter, an air-conditioning controller, and a contactor is arranged midway along a passageway for in-vehicle air. With this configuration, the electrical component box is cooled by in-vehicle air taken in through the return port.
Patent Literature 1 discloses a vehicle air-conditioning apparatus which is composed of a compressor, an outdoor heat exchanger, an indoor heat exchanger, an outdoor fan, an indoor fan, and an electrical component box, wherein an outdoor unit chamber housing the compressor, the outdoor heat exchanger, and the outdoor fan and an indoor unit chamber housing the indoor heat exchanger, the indoor fan, and the electrical component box are coupled with each other such that the compressor and an inverter are located back-to-back.